The present invention relates to a process for the aminolysis of ethylene polymers and in particular, ethylene-alkyl acrylate copolymers.
Ethylene polymers and ionomers and, in particular, co- and terpolymers such as poly(ethylene-co-acrylamide-co-sodium acrylate) can be effectively employed within a variety of environments depending on their mechanical and optical properties.
For example, certain of these ethylene-containing polymers can be employed in place of traditional polyolefins within adhesive compositions. Moreover, such polymers can replace polyacrylamide homopolymers in water treatment, beer and wine clarification, food processing, and the like. One particular useful environment involves the use of the polymers within multilayer films.
While the art is capable of producing such polymers, it has been largely ineffective in providing a continuous method for producing polymers having certain desired mechanical and optical properties, particularly on an industrial scale.
For example, batch ammonolysis of alkylene-alkyl acrylate polymers is recognized within the art. In particular, U.S. Pat. No. 3,429,860 to Hurst relates to a batch process for the ammonolysis of ethylene-alkyl acrylate copolymers utilizing an aqueous ammonia solution in the presence of a minor quantity of an alkali metal hydroxide and an inert solvent. However, this batch process, which occurs within a heated reactor, requires a reaction time on the order of 2-20 hours and further requires a costly post-reaction washing of the product in order to obtain the desired product in a finely divided form. Because of these limitations, such a process cannot be effectively employed on an industrial scale.
Accordingly, the need still exists for a process which overcomes such deficiencies and is capable of effectively providing a desired ethylene copolymer.